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Re: So what's null then if it's not nothing?

From: Roy Hann <specially_at_processed.almost.meat>
Date: Wed, 23 Nov 2005 09:01:40 -0000
Message-ID: <0uadnR6IPq2lrRneRVnyrg@pipex.net>


<michael_at_preece.net> wrote in message
news:1132523923.003424.300650_at_g49g2000cwa.googlegroups.com...
> This just seems plain wrong to me. It surely is an empty set - or an
> empty thing. The thing surely exists.

               ^^^^^^^^^^^^^^^^^^^^^^^^

No it doesn't, or at least not the way null columns in SQL databases are almost universally used. Many (perhaps most) of the databases I look at have at least a few table that mix multiple entity types in one table, and then count on being able to use nulls to insert a row where the thing does *not* logically exist.

I think this is a fundamentally different (mis-)use of nulls.

Roy Received on Wed Nov 23 2005 - 03:01:40 CST

Original text of this message

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